Answer:
Since the meeting of Ally leaders in Casablanca they have discussed about new front in Europe that will relax Eastern front and will led to victory of Allied forces. That is why when the beaches of Normandy were attacked on July 6, 1944 Germans had to employ a lot of troops to defend the shores. Their defense was unsuccessful and with the victory of Anglo-American troops allies came one step to closer to ending the war.
Step-by-step explanation:
After the Allied forced attacked Sicily it was more than obvious that war will have to spread to Western Europe. That is what Soviet also asked. There were several plans and the one to land in Normandy prevailed. Allies totally defeated German troops which eventually led to them winning the war.